1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22/* 23 * Copyright (c) 1988 AT&T 24 * All Rights Reserved 25 * 26 * 27 * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 28 * Use is subject to license terms. 29 */ 30#pragma ident "%Z%%M% %I% %E% SMI" 31 32/* 33 * Bootstrap routine for run-time linker. 34 * We get control from exec which has loaded our text and 35 * data into the process' address space and created the process 36 * stack. 37 * 38 * On entry, the process stack looks like this: 39 * 40 * # # <- %rsp 41 * #_______________________# high addresses 42 * # strings # 43 * #_______________________# 44 * # 0 word # 45 * #_______________________# 46 * # Auxiliary # 47 * # entries # 48 * # ... # 49 * # (size varies) # 50 * #_______________________# 51 * # 0 word # 52 * #_______________________# 53 * # Environment # 54 * # pointers # 55 * # ... # 56 * # (one word each) # 57 * #_______________________# 58 * # 0 word # 59 * #_______________________# 60 * # Argument # low addresses 61 * # pointers # 62 * # Argc words # 63 * #_______________________# 64 * # argc # 65 * #_______________________# <- %rbp 66 * 67 * 68 * We must calculate the address at which ld.so was loaded, 69 * find the addr of the dynamic section of ld.so, of argv[0], and of 70 * the process' environment pointers - and pass the thing to _setup 71 * to handle. We then call _rtld - on return we jump to the entry 72 * point for the a.out. 73 */ 74 75#if defined(lint) 76 77extern unsigned long _setup(); 78extern void atexit_fini(); 79void 80main() 81{ 82 (void) _setup(); 83 atexit_fini(); 84} 85 86#else 87 88#include <link.h> 89 90 .file "boot.s" 91 .text 92 .globl _rt_boot 93 .globl _setup 94 .globl _GLOBAL_OFFSET_TABLE_ 95 .type _rt_boot,@function 96 .align 4 97 98_rt_alias: 99 / in case we were invoked from libc.so 100 jmp .get_got 101_rt_boot: 102 / save for referencing args 103 movq %rsp,%rbp 104 / make room for a max sized boot vector 105 subq $EB_MAX_SIZE64,%rsp 106 / use esi as a pointer to &eb[0] 107 movq %rsp,%rsi 108 / set up tag for argv 109 movq $EB_ARGV,0(%rsi) 110 / get address of argv 111 leaq 8(%rbp),%rax 112 / put after tag 113 movq %rax,8(%rsi) 114 / set up tag for envp 115 movq $EB_ENVP,16(%rsi) 116 / get # of args 117 movq (%rbp),%rax 118 / one for the zero & one for argc 119 addq $2,%rax 120 / now points past args & @ envp 121 leaq (%rbp,%rax,8),%rdi 122 / set envp 123 movq %rdi,24(%rsi) 124 / next 125.L0: addq $8,%rdi 126 / search for 0 at end of env 127 cmpq $0,-8(%rdi) 128 jne .L0 129 / set up tag for auxv 130 movq $EB_AUXV,32(%rsi) 131 / point to auxv 132 movq %rdi,40(%rsi) 133 / set up NULL tag 134 movq $EB_NULL,48(%rsi) 135 136 / arg1 - address of &eb[0] 137 movq %rsi, %rdi 138.get_got: 139 leaq _GLOBAL_OFFSET_TABLE_(%rip), %rbx 140 / addq $_GLOBAL_OFFSET_TABLE_, %rbx 141 movq %rbx,%r9 142 // addq $[.L2-.L1], %rbx 143 movq %rbx,%r10 144 145 movq (%rbx),%rsi 146 147 / _setup(&eb[0], _DYNAMIC) 148 call _setup@PLT 149 / release stack frame 150 movq %rbp,%rsp 151 152 movq atexit_fini@GOTPCREL(%rip), %rdx 153 / transfer control to a.out 154 jmp *%rax 155 .size _rt_boot,.-_rt_boot 156#endif 157